S-(phthalazin-1-yl)- and 5-(1h-1,2,4-triazol-5-yl)-thioazoles and dithiocarbamates



United States Patent US. Cl. 260-250 4 Claims ABSTRACT OF THE DISCLOSURES-(Phthalazin-1-y1)- and S- 1H-1,2,4-triazol-Syl) -thioazoles,thiopyrimidines, and dithiocarbamates are described which are useful foraccelerating vulcanization of rubber.

This application is a division of Ser. No. 513,558, filed Dec. 13, 1965,now patent No. 3,379,700, issued Apr. 23, 1968.

This invention relates to derivatives of phthalazine and1H-l,2,4-triazole. The invention further relates to new chemicalcompounds useful as vulcanization accelerators in rubber.

An objet of this invention is to provide new and useful chemicalcompounds for industry. A further object of this invention is to promotethe progress of science and useful arts. Other objects will becomeapparent as the description proceeds.

The new compounds of the invention may be represented by the formulaT-S-C 5 In general, T is a radical having carbon attached to the sulfurshown, which carbon in turn is either singly or doubly linked tonitrogen. T may be thiazole, oxazole,

imidazole, a pyrimidine ring, or thiocarbamoyl. More particularly, T maybe 4,6 di(lower alkyl)-pyrimidin-2- yl or wherein R and R are loweralkyl, lower cycloalkyl, aryl preferably of the benzene series, or R andR taken together are an open chain radical which with the nitrogenconstitute a heterocyclic ring which preferably contains at least fivemembers, at least four of which are carbon and not more than one isnitrogen. T may be wherein A is orthophenylene either unsubstituted orsubstituted by one or more halogen, lower alkyl, or lower alkoxysubstituents and Z is oxygen, sulfur, or NH. And T may be R"CN whereinR" is lower alkyl-C-, carbamoyl, carbanilino, carboxy, or hydrogen and Ris lower alkyl. For example, where the radical is lH-1,2,4-triazol-5ylor phthalazin-l-yl, T may be N- alkyl-N-aryl thiocarbamoyl,N,N-(oxapentamethylene)- thiocarbamoyl, N,N-diloweralkyl thiocarbamoyl,4,6 dimethyl-pyrirnidin 2 yl, 4-methyl-thiazol-2-yl, (4-methyl 5acetyl)-thiazol-2-yl, (4-methyl-5-carbamoyl)thiazol-2-yl,(4-methyl-5-carbanilino)thiazol-2-yl, (4-methyl- 5-carboxy)thiazol-2-yl,N,N hexamethylene thiocarbamoyl, or an unsubstituted 2 benzothiazolyl, 2benzoxazolyl or Z-benzimidazolyl radical or a substituted2-benzothiazolyl, 2-benzoxazolyl or 2-benzimidazolyl radical substitutedin the 5 or 6 position with a halogen or lower alkoxy radical. In thisinvention, the term lower includes 1 to 8 carbon atoms.

Suitable examples of the compounds of this invention are:

1- 2-benzothiazolylthio) phthalazine,

S-(phthalazin-1-yl)N,N-3-oxapentamethylenedithiocarbamate,

S- (phthalazinl-yl) N,N-diethyldithiocarbamate,

1- 6-ethoxy-2-benzothiazolylthio phthalazine,

1- (5-chloro-2-benzothiazolylthio phthalazine,

1- Z-benzoxazolylthio) phthalazine,

1- Z-benzimidazolylthio phthalazine,

1- (4-methyl-5-acetyl-2-thiazolylthio phthalazine,

S- (phthalazin- 1 -yl) N,N-tetramethylenedithiocarb amate,

S- (phthalazinl-yl N,N-pentamethylenedithiocarbamate,

S- (phthalazinl-yl N,N-hexamethylenedithiocarb amate,

S- (phthalazinl-yl N,N-dimethyldithiocarbamate,

S-(phthalazin-1-yl)N,N-diisopropyldithiocarbamate,

1- (4-methyl-5-carbamoyl -2-thiazolylthio] phthalazine,

1- (4-methyl-2-thiazolylthio) phthalazine,

1- (4-methyl-5-carbanilino -2-thiazolylthio] phthalazine,

1-[ (4-methyl-5-carboxy -2-thiazolylthio] phthalazine,

1- (4,6-dimethyl-2-pyrimidinylthio) phthalazine,

S-(1H-1,2,4-triazol-5-yl)N,N-dipropyldithiocarbamate,

S-( 1H-1,2,4-triazol-5-yl)N-ethyl-N-cyclohexyldithiocarbamate,

S-( lH-l,2,4-triazol-S-yl N,N-dibutyldithiocarbamate,

S- lH-l ,2,4-triazol-5-yl) N,N-diethyldithiocarbamate,

S-( 1H-l,2,4-triazol-5-yl)N-ethyldithiocarbanilate,

5- (Z-benzothiazolylthio) lH-1,2,4-triazole,

S-( 1H-1,2,4-triazol-5-yl)N,N-3-oxapentamethylenedithiocarbamate,

5- 6-ethoxy-2-benzothiazolylthio) lH-1,2,4-triazole,

5- 5-chloro-2-benzothiazolylthio) 1H-1,2,4-triazole,

5- 2-benzoxazolylthio) lH-1,2,4-triaz0le,

5- (Z-benzimidazolylthio) 1H-1,2,4-triazole,

5 (4-rnethyl-5-acetyl-2-thiazolylthio) 1H- 1 ,2,4-triazole,

S-( lH- 1,2,4-triazol-5-yl) N,N-tetramethylenedithiocarbamate,

S-(1H-1,2,4-triazol-5-yl)N,N-pentamethylenedithiocarbamate,

S-( lH-1,2,4-triazol-5-yl) N,N-hexamethylenedithiocarbamate,

S-( lH-l ,2,4-triazol-5-yl N,N-dimethyldithiocarbamate,

S-(1H-1,2,4-triazol-5-yl)N,N-diisopropyldithiocarbamate,

5- (4-methyl-5-carbamoyl) -2-thiazolylthio] 1H-1,2,4-

triazole,

5-(4-methyl-2-thiazolylthio) lH-l ,2,4-triazole,

5- Lmethyl-S-carbanilino -2-thiazolylthio] lH- 1,2,4-

triazole,

5-[ (4-methyl-5-carboxy) -2-thiazolylthio] 1H-1,2,4-triazole,

5 (4,6-dimethyl-2-pyrimidinylthio) 1H- 1 ,2,4-triazole,

S- (phthalazin-l -yl) N,N-dipropyldithiocarb amate,

S-(phthalazin-1-yl)N-methyl N-cyclohexyldithiocarbamate,

S- (phthalazin-l-yl N,N-dibutyldithiocarb amate, and

S- (phthalazin-l-yl N-ethyldithiocarbanilate.

The new compounds of this invention are prepared as follows.

The compound 1-(2-benzothiazolylthio)phthalazine is prepared by addingin one portion 16.5 grams (0.1 mole) of l-chloro phthalazine to astirred solution containing 17.2 grams (0.1 mole) of 97%Z-mercaptobenzothiazole, 300 ml. of ethyl alcohol, and 6.3 grams (.1mole) of 90% potassium hydroxide. The stirred reaction mixture is heatedat 75 80 C. for 24 hours. The mixture is cooled to 25 C. and 500 ml. ofwater is added. Stirring is continued for 15 minutes at 25 -30 C. Theresulting solid is collected by filtration, washed with water untilneutral to litmus and air dried at 25 -30 C. The product, melting point166 -18 C., is obtained in an 88% yield. After recrystallization fromethyl alcohol, a sample of the product melts at l72l73 C. Analysis ofthe l-(2-benzothiazolylthio)phthalazine shows 14.12% nitrogen and 21.62%sulfur. Calculated percentages for C H N S are 14.23% nitrogen and21.70% sulfur. The infrared spectrum confirms the structure of1-(2-benzothiazolylthio)phthalazine.

The compound 1 (6 ethoxy 2 benzothiazolylthio)- phthalazine is preparedin a similar manner as described above except 21.2 grams (0.1 mole)6-ethoxy-2-rnercaptobenzothiazole is used as a reactant in place ofZ-mercaptobenzothiazole and the reaction is stirred at reflux for fivehours. The product, melting point 130-135 C., is obtained in a 62.4%yield. After recrystallization from an ethyl alcohol acetone mixture, asample of the product melts at 141 -143 C. Analysis of the1-(6-ethoxy-2- benzothiazolylthio)phthalazine shows 12.62% nitrogen and18.83% sulfur. Calculated percentages for r'r ra a z are 12.39% nitrogenand 18.87% sulfur.

The compound 1 chloro 2 benzothiazolylthio) phthalazine is prepared in asimilar manner as described above except 20.2 grams (0.1 mole) of5-chloro-2-mercaptobenzothiazole is used as a reactant in place of 2-mercaptobenzothiazole. The product, melting point 199- 201 C., isobtained in a 70% yield. After recrystallization from benzene, a sampleof the product melts at 204- 205 C. Analysis of the1-(5-chloro-2-benzothiazolylthio) phthalazine shows 12.59% nitrogen,19.12% sulfur and 10.60% chlorine Calculated percentages for are 12.74%nitrogen, 19.44% sulfur, and 10.75% chlorine.

The compound 1-[(4-methy1-5-carbamoyl)-2-thiazolylthio]phthalazine isprepared in a similar manner as described above except 17.4 grams (0.1mole) of 2-mercapto-4-methyl-5-carbamoyl thiazole is used as a reactantin place of Z-mercaptobenzothiazole. The product, melting point 228-229C., is obtained in a 73% yield. Analysis of the 1 [(4methyl-S-carbamoyl)-2-thiazolylthio] phthalazine shows 18.28% nitrogenand 20.74% sulfur. Calculated percentages for C H N OS are 18.53%nitrogen and 21.21% sulfur.

The compound 1-(4-methyl-2-thiazolylthio)phthalazine is prepared in asimilar manner as described above except 13.2 grams (0.1 mole)2-mercapto-4-methylthiazole is used as a reactant in place ofZ-mercaptobenzothiazole. The product, melting point 117-120 C., isobtained in a 69.5% yield. After recrystallization from ethyl alcohol, asample of the product melts at l24125 C. Analysis of the1-(4-methyl-2-thiazolylthio)phthalazine shows 15.85% nitrogen and 24.17%sulfur. Calculated percentages for C H N S are 16.20% nitrogen and24.73% sulfur.

The compound 1-[(4-methyl-5-carbanilino)-2-thiazolylthio]phthalazine isprepared by adding in one portion 10 grams (0.0605 mole) of l-chlorophthalazine to a stirred solution containing 15.2 grams (0.0605 mole)2-mercapto- 4-methyl-5-carbanilino thiazole, 300 m1. ethyl alcohol and3.8 grams (0.0605 mole) 90% potassium hydroxide. The procedure issimilar to the one described above. The product, melting point 214-2l6C., is obtained in a 69.9% yield. After recrystallization fromdimethylformamide, a sample of the product melts at 224-226 C. Analysisof the 1 [4 methyl-S-carbanilino)-2-thiazolylthio]phthalazine shows14.10% nitrogen and 16.59% sulfur. Calculated percentages for C H N OSare 14.81% nitrogen and 16.95% sulfur.

The compound 1- (4-methyl-5-acetyl-2-thiazolylthio)- phthalazine isprepared in a similar manner as described above except 17.3 grams (0.1mole) 2-mercapto-4-methyl- S-acetyl thiazole is used as a reactant inplace of 2- mercaptobenzothiazole. The product, melting point 199 202"C., is obtained in a 91.2% yield. After recrystallization fromdimethylformamide, a sample of the product melts at 206-207 C. Analysisof the 1-(4-methyl-5- acetyl-Z-thiazolylthio)phthalazine shows 13.54%nitrogen and 20.88% sulfur. Calculated percentages for 1-(4- methyl 5acetyl-2-thiazolylthio)phthalazine are 13.94% nitrogen and 21.28%sulfur.

The compound 1 (2 benzoxazolylthio)phthalazine is prepared in a similarmanner as described above except 15.1 grams (0.1 mole)2-mercaptobenzoxazole is used as a reactant in place of2-mercaptobenzothiazole. The product, melting point 152l54 C., isobtained in a 68% yield. After recrystallization from ethyl alcohol, asample of the product melts at 162-163 C. Analysis of the 1-(2-benzoxazolylthio)phthalazine shows 15.02% nitrogen and 10.60% sulfur.Calculated percentages for C H N OS are 15.05% nitrogen and 11.48%sulfur.

The compound l-(2-benzimidazolylthio)phthalazine is prepared in asimilar manner as described above except 15.1 grams (0.1 mole)Z-mercaptobenzimidazole is used as a reactant in place ofZ-mercaptobenzothiazole. The product, melting point 188190 C., isobtained in a 45.2% yield. After recrystallization from ethyl alcohol, asample of the product melts at 191192 C. Analysis of the1-(2-benzimidazolylthio)phthalazine shows 19.59% nitrogen and 11.57%sulfur. Calculated percentages for C H N S are 20.13% nitrogen and11.52% sulfur.

The compound 1 (4,6 dimethyl 2-pyrimidinylthio) phthalazine is preparedby adding in one portion 33 grams (0.2 mole) of l-chloro phthalazine toa stirred solution containing 35.4 grams (0.2 mole)4,6-dimethyl-2-pyrirnidinethiol hydrochloride, 600 ml. ethyl alcohol and26.4 grams (0.4 mole) potassium hydroxide. The procedure is similar tothe one described above, The product, melting point 184 186 C., isobtained in an 18.7% yield. After recrystallization from ethyl alcohol,a sample of the product melts at l89l90 C. Analysis of the1-(4,6-dimethyl-2-pyrimidinylthio)phthalazine shows 20.35% nitrogen and11.71% sulfur. Calculated percentages for C H N S are 20.88% nitrogenand 11.95% sulfur.

The preparation of 1 [(4 methyl 5-carboxy)-2-thiazolylthio]phthalazineis illustrated by the following reaction.

CHaC=CCOOCrHs The l-chloro phthalazine (16.5 g.) is added in one portionto a stirred solution containing 20.4 grams (0.1 mole) of2-mercapto-4-methyl-5-ethoxy carbonyl thiazole, 200 ml. ethyl alcohol,and 6.3 grams (0.1 mole) of 90% potassium hydroxide. The reactionmixture is stirred at 25-30 C. for 24 hours. Then the reaction mixtureis added to 1000 grams of Water and stirred at 10 C. for 30 minutes.Filtration removes the small amount of impurities. Concentratedhydrochloric acid is added slowly to the stirred filtrate until a pH of4 is obtained. The resulting solid is collected by filtration, washedwith water until neutral to litmus and air dried at 25 30 C. Theproduct, melting point 163166 C., is obtained in a 75.6% yield. Afterrecrystallization from ethyl acetate, a sample of the product melts at174-175 C. Analysis of the1[(4-methyl-5-carboxy)-2-thiazolylthio]-phthalazine shows 13.36%nitrogen and 21.40% sulfur. Calculated percentages for C H N O S are13.85% nitrogen and 21.14% sulfur. The infrared spectrum confirms thestructure of 1 [(4 methyl-S-carboxy)-2-thiazolylthio] phthalazine.

The compound S (phthalazin 1-yl)-N,N-3-oxapentamethylenedithiocarbamateis prepared by adding slowly 7.6 grams (0.1 mole) of carbon disulfide toa stirred solution containing 8.7 grams (0.1 mole) of morpholine, 200ml. of ethyl alcohol, and 16 grams (0.1 mole) of 25% aqueous sodiumhydroxide. After stirring at 25 30 C. for one hour, 16.5 grams (0.1mole) of 1-chlorophthalazine is added in one portion. The stirredreaction mixture is heated at 75 -80 C. for 24 hours. After cooling to25 C., 600 ml. of water is added and stirred at 0l0 C. for 15 minutes.The solid is collected by filtration, washed with water until neutral tolitmus and air dried at 25 -30 C. The product, melting point 153- 155C., is obtained in an 82.5% yield. After recrystallization fromdimethylformamide, the melting point of a sample of the product is 183-184 C. Analysis of the S(phthalazin-l-yl)-N,N-3-oxapentamethylenedithiocarbamate shows 14.37%nitrogen and 22.03% sulfur. Calculated percentages for C H N OS are14.42% nitrogen and 22.00% sulfur.

The compound S-(phthalazin-1-yl)N,N-diethyldithiocarbamate is preparedin a similar manner as the S- (phthalazin 1yl)-N,N-3-oxapentamethylenedithiocarbamate described above except 7.3grams (0.1 mole) of diethylamine is used in place of morpholine and thestirred reaction mixture is heated at 5060 C. for six hours. Aftercooling to 25 C., 300 ml. of water and 400 ml. of ethyl ether are added.After stirring for 15 minutes, the separated ether layer is Washed withwater until neutral to litmus and dried over sodium sulfate. The etheris removed in vacuo at a maximum temperature of 30 C. at -12 mm. Hg. Theresulting solid is air dried at 25 30 C. The product, melting point 85-90 C., is obtained in a 65% yield. After recrystallization from ethylalcohol, a sample of the product melts at 109- 110 C. Analysis of theS-(phthalazin-1-yl)N,N-diethyldithiocarbamate shows 15.10% nitrogen and23.93% sulfur. Calculated percentages for C H N S are 15.15% nitrogenand 23.12% sulfur.

The compound S-(phthalazin-l-yl)N,N-hexamethylenedithiocarbamate isprepared in a similar manner as S- (phthalazin 1yl)N,N-3-oxapentamethylenedithiocarbamate described above except 10grams (0.1 mole) hexamethylenimine is used as a reactant in place ofmorpholine. The product, melting point 140-l43 C., is obtained in a 99%yield. After recrystallization from ethyl alcohol, a sample of theproduct melts at 153- 154 C. Analysis of theS-(phthalazin-l-yl)N,N-hexamethylene dithiocarbamate shows 13.37%nitrogen and 20.60% sulfur. Calculated percentages for C15H17N3S2 are13.85% nitrogen and 21.13% sulfur.

The compound S-(phthalazin-1-yl)N,N-dimethyldithiocarbamate is preparedin a similar manner as S-(phthalazin 1 yl)N,N-3-oxapentamethylenedithiocarbamate described above except 18 grams(0.1 mole) of 25% dimethylamine is used as a reactant in place ofmorpholine. The product, melting point 122127 C., is obtained in an 88%yield. After recrystallization from ethyl alcohol, a sample of theproduct melts at 150152 C. Analysis of theS-(phthalazin-l-yl)N,N-dimethyldithiocarbamate shows 16.34% nitrogen.The calculated percentage for C H N S is 16.85% nitrogen.

The compound S (phthalazin 1-yl)N,N-diisopropyldithiocarbamate isprepared in a similar manner as S- (phthalazin 1yl)-N,N-3-oxapentamethylenedithiocarbamate described above except 10.1grams (0.1 mole) diisopropylamine is used as a reactant in place ofmorpholine. The product, melting point 140l45 C., is obtained in a 39.2%yield. After recrystallization of a sample of the product from analcohol-acetone mixture, the melting point is 191-192 C. Analysis of theS- (phthalazin 1 yl)N,N diisopropyldithiocarbamate shows 13.54%nitrogen. The calculated percentage for C15H1 N3Sz is nitrogen.

The compound S-(1H-1,2,4-triazol-5-yl)N,N-dipropyldithiocarbamate isprepared by heating at 55 -56 C. for 30 minutes a charge containing 40.4grams (0.4 mole) of 1,2,4-triazole-5-thio, 800 ml. of acetone, and 25.2grams (0.4 mole) of 90% potassium hydroxide. After cooling to 25 C.,71.6 grams (0.4 mole) of dipropylthiocarbonyl chloride is added in oneportion. The stirred mixture is heated at 55-56 C. for five hours andthen filtered hot to remove the potassium chloride. The filtrate isadded to 2000 grams of ice water and stirred at 0- 10 C. for one hour.The precipitate is collected by filtration, washed with water untilneutral to litmus, and air dried at 25-30 C. The product, melting point90- C., is obtained in a 65.5% yield. After recrystallization from ethylacetate, a sample of the product melts at 1171l9 C. Analysis of theS-(1H-l,2,4-triazol-5- yl)N,N-dipropyldithiocarbamate shows 22.45%nitrogen and 26.31% sulfur. Calculated percentages for C H N S are22.93% nitrogen and 26.24% sulfur.

The compound S-(1H-1,2,4-triazol-5-yl)N,N-dibutyldithiocarbamate isprepared by adding 41.6 grams (0.2 mole) of dibutylthiocarbonyl chlorideto a stirred solution containing 20.2 grams (0.2 mole)1H-1,2,4-triazole- S-thiol, 300 ml. acetone, 20 ml. of water, and 12.6grams (0.2 mole) 90% potassium hydroxide, and the mixture is stirred at25 -30 C. for 24 hours. After the addition of 300 ml. of water and 400ml. of ethyl ether, the reaction mixture is stirred at 25 30 C. for 15minutes. The separated ether layer is washed with water until thewashings are neutral to litmus and then dried over sodium sulfate. Theether is removed in vacuo at a maximum temperature of 80-90 C. at 1-2mm. Hg. The product, a black-colored liquid, is obtained in a 77% yield.Analysis of the S-(1H-1,2,4-triazol-5-yl)N,N-dibutyldithiocar-bamateshows 20.36% nitrogen. The calculated percentage for C H N S is 20.57%nitrogen.

The compound S-(1H-1,2,4-triazol-5-yl)N,N-diethyldithiocarbamate isprepared in a similar manner as S-(1H-1,2,4-triazol-5-yl)N,Ndipropyldithiocarbamate described above except 60.4 grams (0.4 mole) ofdiethylthiocarbonyl chloride is used in place of dipropylthiocarbonylchloride. The product, melting point 158 -161 C., is obtained in a 52%yield. After recrystallization from ethyl alcohol, a sample of theproduct melts at 172- 173 C. Analysis of theS-(1H-1,2,4-triazo1-5-yl)N,N-diethyldithiocar-bamate shows 25.41%nitrogen. The calculated percentage for C H N S is 25.90% nitrogen.

The compound S-(1H-1,2,4 triazol 5-yl)N-ethyldithiocarbanilate isprepared in a similar manner as S-(1H-1,2,4 triazol5-yl)N,Ndipropyldithiocarbamate described above except 80 grams (0.4 mole)N-ethyl-N- phenyl thiocarbonyl chloride is used in place ofdipropylthiocarbonyl chloride. The product, melting point 148 C., isobtained in a 68.5% yield. After recrystallization from ethyl alcohol, asample of the product melts at 191192 C. Analysis of theS-(1H-1,2,4-triazol-5- yl)-N-ethyl dithiocarbanilate shows 20.36%nitrogen. Stock Compound The calculated percentage for C H N S is 21.19%6 1-(2-benzlmldazolylthlo)phthalazine. nitrogen. The remaining compoundsof this invention are 7 1-(4-methyl 2-th1azolylthlo)phthalaprepared in asimilar manner to the preparations dezine. scribed, supra, withcomparable results. r 8 l[(4-methyl S-carboxy) 2 thlazolyl The followingtables illustrate the useful properties thlo]phthalazlne. of thecompounds of this invention as vulcanization ac- 9 1-(4-methyl acetyl 2thlazolylcelerators in sulfur vulcanizable rubber. For the rubberthio)phthalazlne. stocks tested and described below, as illustrative ofthe 1[(4-methyl S-carbamoyl) 2-th1autility, Mooney scorch times aredetermined by means 10 zolylthlolphthalazlne. of a Mooney plastometer.The time represents the .11 1-[(4 methyl 5 carbanilino) 2- time inminutes required for the Mooney reading to thiazolylthio]phthalazine.rise five points above the minimum viscosity of the 12 MBT.

TABLE I Cure Time Stock (Mins.) at

A-l Masterbatch 161 161 161 161 161 161 161 161 161 161 161 161 NeozoneD.- 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Sulfur 2.5 2.5 2.52.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Accelerator 0.5 0.62 0.69 0.69 0.590.58 0.54 0.64 0.63 0.63 0.79 0.35 Mooney Scorch at 135 0., t 9. 7 8.83. 7 9. 3 9.1 12. 8 8.0 5. 3 9. 5 17. 5 10.3 5. 0 Stress-Strain:

Modulus 300, psi 2, 650 2,340 2, 050 2, 300 1, 470 1, 200 2, 430 2, 4502, 390 1, 440 2, 050 2,050 2, 560 2,340 2, 000 2, 340 1, 590 1, 270 2,600 2, 500 2, 430 1,730 2, 200 2, 050 2, 560 2, 280 2, 050 2, 1, 570 1,460 2, 360 2, 480 2, 430 1,320 2, 200 2, Ultimate Tensile Strength,p.s.i 30 4,050 3,900 3, 900 4,000 2, 500 2, 030 4, 310 3, 220 3, 7402,340 3, 740 3, 430 45 4,500 3, 640 3, 330 3, 750 2, 460 2,430 3, 940 3,170 3,900 2,740 3, 320 00 4, 250 3, 640 3, 490 3, 400 2, 430 2, 050 4,050 2, 450 3, 700 2, 460 3, 280 3, 360 Ultimate Elongation,Percent 30470 500 500 400 450 450 490 400 450 450 430 430 rubber. The knownaccelerators, MBT, Santocure, and Santocure NS, are included in the datafor comparison purposes. MBT designates 2-rnercaptobenzothiazole,

Table 11 illustrates rubber cure properties of the compounds of thisinvention in an A-S masterbatch. An A-5 masterbatch is composed of:

and Santocure NS is the trademark for N-tert-butyl-Z- Partsbenzothiazolesulfenamide. Santocure is the trademark 39 Natural rubbersmoke sheets 100 for N-cyclohexyl-Z-benzothiazole sulfenamide. The anti-High abrasion furnace black 50 oxidant Neozone D is included in thestocks. The active Zinc oxide 3.0 ingredient for Nezone D is reported tobe N-phenyl- Stearic acid 2.0 beta naphthylamine. An A-l masterbatch asused in 40 Hydrocarbon softener 3.0 Table I is composed of: Saturatedpolymerized petroleum hydrocarbon 3.0 Parts The numerical stocks 3through 7 in Table II represent 'f TuPber Smoke sheets 100 rubbercontaining the compounds of this invention. The furnace black 50 stocknumbers in Table II contain the following StFanc \afild 3 45 compounds.Zmc Oxlde n 5 Stock Compound H drocarbon softener 3 y 1 Santocure NS.

Total arts 161 2 p 3 S-(lH-l,2,4-trlazol-5-yl)N,N-dipropyld1th1o- Thenumerical stocks 2 through 11 in Table I represent 50 carbamate rubbercontaining the compounds of this invention. The 4 s 4 i 1-5 1 h 1 i istocks in Table I contain the following compounds. carbamate StockCompound 5 S-(phthalazin-l-yl)N,N-3-oxapentamethylene 1 Santocuredithiocarbamate. 2 1-(Z-benzothiazolylthio)phthalazine. g g ig fl iii zg f'if g ft t g fi 3 1-(6-ethoxy 2 benzothiazolylthio) t 5 Yamatephthalazine. Although dithiocarbamates are not generally delayedac- 4 1-(5-chloro 2 benzothiazolylthio) tion accelerators,S-(phthalazin-l-yl)N,N-3-oxapentaphthalazine. 6Omethylenedithlocarbamate is an exception according to 51-(2-benzoxazolylthio)phthalazine. the Mooney Scorch of 10.6 minutesreported in Table II.

TABLE II Cure Time Stock (Mins.) at 144C. 1 2 3 4 5 6 7 11-5 Masterbatch161 161 161 161 161 161 161 Neozone D 1. 0 1. 0 1. 0 1. 0 1. 0 1. 0 1. Osullur 2.5 2.5 2.5 2.5 2.5 2.5 2.5 Accelerator 0. 5 0. 5 0. 5 0. 5 0. 50. 5 0. 5 Mooney Scorch at 0., t 10.0 5.1 7.4 7.3 10.6 4.7 9.6Stress-Strain:

Modulus 300, p.s.i 45 2,680 2,200 2,170 2,170 1,750 2,230 1,810 60 2,7002,270 2,040 1,950 1,690 2,220 1,680 Ultimate Tensile stren th, p.s.1..-45 4,250 3,510 3,460 3,560 2,770 3,460 3,040 60 4,000 3,220 3,560 2,4702,590 3,590 2,030 Ultimate Elongation, Percent 45 450 460 450 480 420440 450 60 430 400 490 360 400 480 400 The compound1-(4,6-dimethyl-Z-pyrimidinylthio)1 phthalazine is an accelerator forthe vulcanization of rub ber comparable to MBT but much less scorchythan MBT. The Mooney Scorch reading t at 135 C. for a natural rubberstock containing MBT shows five minutes. The 5 same stock without MBTbut containing l-(4,6-dimethyl- Z-pyrimidinylthio)phthalazine shows 10.7minutes for t The remaining compounds of this invention are also usefulvulcanization accelerators in rubber.

It is intended to cover all changes and modifications of the examples ofthe invention herein chosen for purposes of disclosure which do notconstitute departures from the spirit and scope of the invention.

I claim: 1. A compound of the formula i s-0 i wherein is phthalazin-l-yland T is Z A/ \G wherein Z is oxygen, NH or sulfur and A isorthophenylene, chloroorthophenylene, lower alkylorthophenylene or loweralkoxyorthophenylene; or

R"C-S R/II wherein R is lower alkyl carbamoyl, carbanilino, carboxy orhydrogen and R' is lower alkyl.

2. A compound according to claim 1 wherein T is 2-benzothiazolyl, havingthe name 1-(2-benzothiazolylthio)phthalazine and formula 3. A compoundaccording to claim 1 wherein T is (4-methyl-5-acetyl)thiazol-Z-yl,having the name 1-(4- methyl-S-acetyl-Z-thiazolylthio)phthalazine andformula HsC-C-N No references cited.

ALEX MAZEL, Primary Examiner.

JOSE TOVAR, Assistant Examiner.

US. Cl. X.R.

